Grapefruit knife



FIG. 1 is a top plan view of a grapefruit knife showing my new design;

FIG. 2 is a side elevational view thereof;

FIG. 3 is an opposite side elevational view thereof;

FIG. 4 is an enlarged sectional view taken along line 4--4 in FIG. 2;

FIG. 5 is an enlarged sectional view taken along line 5--5 in FIG. 2; and

FIG. 6 is an enlarged sectional view taken along line 6--6 in FIG. 2. 

The ornamental design for a grapefruit knife, as shown. 